Okay. Now that you know what a popup action is, and you've seen the Slap! action that mIRC comes with, by default, you should be all set to get used to the popup editor.
The first step is to actually figure out how to open the editor. You can do it one of two ways. Either go to Tools and click on Popups, or hit Alt and P at the same time. [screenshot]
Then, you're going to want to go to the View menu within the editor and select Nickname List. This is where you'll be entering your popups, and it's very important that you switch to the Nickname List, or you'll have your actions in the wrong menu. [screenshot]
Scroll down in the editor window, once you've switched to the Nickname List, and you'll see the text for the Slap! action. [screenshot]
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